Improvement in reversible knob-latches



W. M. GRISCOM.

REVERSIBLE KNOB LATCHES. 179.015.

Patented June 20 N. PETERS, PHOTO-LITHOGRAFHER, WASHINGTON, D. C,

U ITED STATES PATENT OFrIoE.

WILLIAM M. GRISOOM, OF READING, PENNSYLVANIA..

I'MPROVEIVlENT IN REVERSIBLE KNOB -LATCHES.

Specification forming part of Letters Patent No. [79,015, dated June 20, 1876 application filed May 25, 1876.

To all whom it may concern:

Be it known that I, WILLIAM M. GRIsooM, of Reading, Pennsylvania, have invented an Improvement in Latch-Locks, of which the following is a specification:

The object of my invention is to so construct a latch-lock that, while considerable resistance is presented to the retraction of the latch-bolt by means of the knob, said bolt may be moved inward by a very slight pressure applied to its end. This object I attain in the following manbeing connected to the inner end of the plate 0, which is ordinarily secured to the stem of the latch-bolt. Against the short arm of the bell-crank lever d bears the inner end of a spring, f, the opposite end ot' which. is secured between lugs on the lock-case, the spring tending to resist the movement of the lever caused by turning the knob to retract the bolt.

The stem 9 of the bolt, instead of being connected directly to the end of the plate 6, as usual, passes through an opening in a lug, h, at the end of the said plate, and has a head at the inner end to prevent its withdrawal, a slot, 6, in the plate, however, permitting the the latchwill operate readily upon the closing of the door; but the desired efl'ect is required to retract it by turning the knob, while, owing to the fact that the spring 12 is confined between the head m of the bolt and the lug h on the plate 0, the removal of the bolt from the control of the casing in order to reverseit may be efi'ectedwithout risking the displacement of the spring, thereby overcoming an objection to looks in which the latch-spring is separate from the bolt and plate. v

I do not desire to claim, broadly, a springlatch which can be moved inwardly independently of the knob mechanism; but

I claim as my invention- The combination of the lever d and plate 0 with the latch on and its spring 19, carried by said plate 6, but so arranged that the latch is capable of moving inwardly independently of the plate, as set forth.

In testimony whereof I have signed myname to tli'is specification in the presence of two subscribing witnesses.

W LLIAM M. GRISOOM.

Witnesses: 4 F. B. RULER, F. M. BANKS. 

